The captain took them to port in Mayport, and then called Burke and asked, "'What are they? How old are they?'"

Burke and a colleague with the Lighthouse Archaeological Maritime Program went to Mayport to measure the anchors and to scour them for any identifying details.

He believes they came from a 19th century ship.

Days later, Burke was training a student how to use sonar on the LAMP research boat, and Burke checked out the area where those two anchors came from.

The sonar "happened to come across one more anchor," Burke explained. "Now we have three anchors."

Sonar images show the outline and shadow of an anchor on the ocean floor.

While he thinks the anchors could even be from a Civil War era ship, he does not know which one at this point.

As for the ship, it's not clear if it's buried or even there.

"A ship in a storm and about to wreck may have let go of all it was carrying in an effort to not wreck," Burke explained.

The underwater site is just north of the St. Augustine Beach Pier and just off the coast. Shrimpers have been over this area a lot, and scientists have surveyed this area before. Still, the anchors have not been discovered until now.

Burke believes, "these have been exposed because of water and changes on the sea bed."

The discovery leads to a stronger relationship between shrimpers and marine archeologists.

"It did damage to their nets and they don't want any more damage done," Burke noted, "and we don't want any historic sites impacted."